1. Field of the Invention
Mailing machines are well known. Typical is the Model 6200 system marketed by Pitney Bowes Inc. of Stamford, Ct. Such systems feed mail which is uniform in weight through postage meters, such as the Model 6500 meter also marketed by Pitney Bowes Inc., so that each mailpiece is metered with indicia corresponding to a pre-selected postage amount. It is also known to connect a postal scale (i.e. a scale which computes the necessary postage amount as a function of the weight of a mailpiece and other information input by an operator) to automatically set the postage meter to the necessary postage amount. Such a system is taught in U.S. Pat. No. 4,286,325; to: Dlugos et al.; issued: Aug. 25, 1985. Attempts have also been made to combine postal scales with mailing machines to develop systems for continuously metering batches of mixed weight mail. Such a system would accept batches of mixed weight mail, singulate the mailpieces, weigh the singulated mailpieces, compute the necessary postage amount, set a postage meter accordingly, and meter the singulated and weighed mailpieces with the necessary postage amount. Such systems have heretofore periodically feed mailpieces onto a continuously operating transport system for transport sequentially through a weighing system and a postage metering system without pause. One such system is taught in U.S. Pat. No. 3,904,946; to: Dlugos et al.; issued: Sept. 9, 1975.
Such known mixed mail systems have several disadvantages. Since the transport system is continuously operating, massive isolation of the weighing system, and expensive balanced components for the transport system are necessary to sufficiently reduce the effects of vibration on the weighing system. Also, continuous transport requires an increased size for mixed weight mailing systems because the weighing system must have a minimum length to assure that the continuously moving mailpiece will be wholly supported by the weighing system for the time necessary to determine its weight. Further, in previously known systems once the transport speed and weighing system length were chosen the time each mailpiece was on the weighing system was fixed and it was not possible to take advantage of improved weigh time capability, resulting from improved scale technology, without a major mechanical re-design of the entire mixed weight mailing system. Thus previously known mixed weight mailing systems have been, in general, large, massive, expensive, systems, suitable only for use by high volume mailers.
"Singulation" (i.e. the separation of exactly one mailpiece from a batch or stack of mailpieces to be processed) has also been a problem in mixed weight mail systems. Mixed weight implies a larger variation in thickness among mailpieces and prior singulating devices capable of handling a large piece to piece range of thicknesses have been complex and expensive, or unreliable.
Thus it is an object of the subject invention to provide a relatively small, less massive, inexpensive, "tabletop" system suitable for use by low and medium volume mailers.
It is another object of the subject invention to provide a mixed weight mailing system where the weighing system is modular and may be easily added to an otherwise substantially conventional mailing machine.
It is still another object of the subject invention to provide a mixed weight mailing system having improved singulating capability.